SIP MWI Mechansims on CUE: “NOTIFY”

Cisco Unity Express uses three type of Message Waiting Indication mechanisms when integrated with a CME or SRST router. All 3 mechanism used are based upon the SIP protocol. Contrast this with the way CUE updates the MWI status on phones registered to UCM- in this instance JTAPI is used.

The focus on this particular article is a technique which relies on the SIP Notify method which is used to tell the CME to light the lamp for a particular extension. An example of a NOTIFY method being received by the CME from the CUE is shown below after the debug ccsip messages command has been used on the CME router.

In this case extension 3002 has a new mail and the picture above is showing the subsequent NOTIFY method.

The CUE Module can be configured to send the NOTIFY  to the CME when phones (and SIP UAs) have subscribed to receive MWI updates using the SUBSCRIBE message.

The first step when configuring the sub-notify mechanism is to select the sub-notify option within the CUE module as shown below:

The sub-notify option can be used concurrently with the outcalling option which is discussed in a separate blog.

Secondly the mwi-server needs to be set up on the CME as shown below:

sip-ua
mwi-server ipv4:10.10.202.2

The SIP-UA and the SCCP-based ephone-dn need to send the SUBSCRIBE method to the mwi server defined in the step above:

voice register dn 1
 number 3005
 mwi
!
ephone-dn 1
number 3001
mwi sip

The above configuration will force the subscription to the mwi service defined on the CUE and now the CUE module will notify the dn’s with an mwi update whenever there is a new voicemail for the appropriate voicemail accounts.

The unsolicited NOTIFY option (notify without subscribe) will force the CUE to send the NOTIFY indicating that a new message has been received on the CUE- in this instance the CME phone does not need to send the SUBSCRIBE method to the mwi server (CUE).

When configuring the unsolicited notify, the CUE module needs to be set up accordingly as shown below:

The voice  register dn and ephone-dn will no longer  need the mwi option configured since the notify will occur without subscription. The mwi-server defined on the CME needs to be set up to receive unsolicited notofy as shown below:

sip-ua
mwi-server ipv4:10.10.202.2 unsolicited

Vik Malhi – CCIE #13890
Instructor – IPexpert, Inc.
Mailto: vmalhi@ipexpert.com

SIP MWI Mechansims on CUE: "NOTIFY", 5.0 out of 5 based on 1 rating

Tags: ccie voice blog, sip mwi, sip protocol